• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.112-112
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• 2017

• 대한기계학회논문집A
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• 제20권12호
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• pp.3767-3781
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• 1996

Generally, dynamic loads are applied to real structures. Since the analysis with the dynamic load is extremely difficult, static loads are utilized by proper conversions of the dynamic loads. The dynamic loads are usually converted ot static loads by safety foactors of experiences. However, it may increase weight and decrease reliability. In this study, a method is proposed for the conversion process. An equivalent static load is calculated ot generate a same maximum displacement. The method is verified through numerical tests on a spring-mass systems of one and multi degrees-of freedom. It has been found that the duration time of the loads and the natural frequencies of the structures are critical in the conversion process. A road arem is a self-propelled howizer is selected for the application of the proposed method. The shape of the road arm is optimized under the converted static loads.

• 한국조경학회지
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• 제34권5호
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• pp.52-58
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• 2006

Wildlife roadkill is a serious problem for road planners and biologists concerned with traffic safety, species conservation, and animal welfare. The objective of this paper was to analyze the effect of land use on the frequency of mammal roadkills. This study took part in three steps. First, data for 1,279 road kills of nine species were collected by survey over 26 months on 107km of roads near the Mt. Jirisan area. Second, the type of land use near the roadkill points was analyzed, and the area of each land use within loom of the road was calculated using GIS. Finally, the question of whether the land use affects the Sequency of mammal roadkills was analyzed by determining the density of roadkill occurrences for each land-use type. The results of the study were as follows. First, the roadkill density of all species was highest near grasslands, especially natural grasslands. Second, when comparing forests and rice fields, roadkill densities of the Eurasian red squirrel, Siberian chipmunk and Korean hare were higher near the forests, while the densities of the raccoon dog, water deer and leopard cat were higher near rice fields. The results of this study could be an essential information source for mitigating the roadkill problem in Korea.

• Journal of Mechanical Science and Technology
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• 제20권1호
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• pp.29-41
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• 2006

Nowadays, with the advancement of computers, computer simulation linked with VR (Virtual Reality) technology has become a useful method for designing the automotive driving system. In this paper, the VR simulation system was developed to investigate the driving performances of the ASV (Advanced Safety Vehicle) equipped with an ACC (Adaptive Cruise Control) system. For this purpose, VR environment which generates visual and sound information of the vehicle, road, facilities, and terrain was organized for the realistic driving situation. Mathematical models of vehicle dynamic analysis, which includes the ACC algorithm, have been constructed for computer simulation. The ACC algorithm modulates the throttle and the brake functions of vehicles to regulate their speeds so that the vehicles can keep proper spacing. Also, the real-time simulation algorithm synchronizes vehicle dynamics simulation with VR rendering. With the developed VR simulation system, several scenarios are applied to evaluate the adaptive cruise controlled vehicle for various driving situations.

• 한국조경학회지
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• 제33권2호
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• pp.83-91
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• 2005

The purpose of this study is to analyze the arrangement of parks, in whole city level by using park's effective distance and to find the accessibility obstacles in case of using parks, in boundary of each parks' effective distance, so that to show how to improve communities' usage of city parks. The 8 cities in Gyeonggi-do and analysed the effective distance of parks. To find the accessibility obstacles in the boundary of parks' effective distance, 1) we choose 18 sample parks and extract obstacles - wide road, rail road, river- in interior and verify it by field survey and asking the park user's residents directly. The main findings of this study can be summarized as follows: First, Ansan city and Goyang city are only satisfied with the minimal city parks size standard, so that the rest 6 cities are lack of quantities which residents can use. The result of analyzing effective distance in whole city level, parks are mainly designated in new-town, so that most cities which have old-towns have very poor park systems to use. Because Ansan city is new-planned city, it is very effective arrangement in park systems exceptionally. Second, $96.2\%$ of park users' are living in the area which was easy to gain access not intercepted by wide road, rail road or river. Third, therefore at the stage of planning park, effective distance and resident's accessibility as well as park's supply quantitatively are needed to be considered. In addition, selection of location and elevation of resident's safety and accessibility through making a plan must be reflected. In the low accessibility area, the program to improve park's accessibility and amenity - like making small park or pocket park, linking parks with resident-friendly road etc.- has to be investigated.

• Wind and Structures
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• 제20권2호
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• pp.213-236
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• 2015

For high-speed railways (HSR) in wind prone regions, wind barriers are often installed on bridges to ensure the running safety of trains. This paper analyzes the effect of wind barriers on the running safety of a high-speed train to cross winds when it passes on a bridge. Two simply-supported (S-S) PC bridges in China, one with 32 m box beams and the other with 16 m trough beams, are selected to perform the dynamic analyses. The bridges are modeled by 3-D finite elements and each vehicle in a train by a multi-rigid-body system connected with suspension springs and dashpots. The wind excitations on the train vehicles and the bridges are numerically simulated, using the static tri-component coefficients obtained from a wind tunnel test, taking into account the effects of wind barriers, train speed and the spatial correlation with wind forces on the deck. The whole histories of a train passing over the two bridges under strong cross winds are simulated and compared, considering variations of wind velocities, train speeds and without or with wind barriers. The threshold curves of wind velocity for train running safety on the two bridges are compared, from which the windbreak effect of the wind barrier are evaluated, based on which a beam structure with better performance is recommended.

• 융합경영연구
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• 제11권2호
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• pp.13-22
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• 2023

Purpose: The purpose of this study is to examine the policy implications of establishing a compact city in Seoul, analyzing whether it is an appropriate and efficient eco-friendly housing supply alternative. Research design, data, and methodology: The analysis criteria include efficiency, safety, and comfort, with efficiency encompassing economic, energy, and public transport links' efficiency. Safety and comfort are aspects of eco-friendliness, housing safety, and improvement in living environments. Results: In terms of economic efficiency, compact cities are a less expensive option than purchasing land for housing construction. To increase energy efficiency, we plan to adopt eco-friendly energy sources. Transportation efficiency is high in locations near public transport stations. To enhance safety and comfort, we intend to create large-scale parks and forests in Seoul. To ensure residential safety, measures will be taken to reduce road vibration, vehicle noise, and scattering dust. Conclusions: Selecting an appropriate location that provides convenient public transportation is essential for creating a compact city for housing in a large city. Combining a compact and smart city is necessary, and implementing smart technologies is needed to prevent dust, noise, and vibrations, which are undesirable in a residential environment.

• 한국자동차공학회논문집
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• 제12권4호
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• pp.163-172
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• 2004

Nowadays, to analyze the dynamic characteristics of the automotive driving system, the computer simulation linked up with VR(Virtual Reality) technology is treated as the useful method with the improvement of computing ability. In this paper, the VR simulation system has been developed to investigate the driving characteristics of the ASV(Advanced Safety Vehicle) equipped with an ACC(Adaptive Cruise Control) system. For the purpose, VR environment which generates 3D graphic and sound information of the vehicle, the road, the facilities, and the terrain has been organized for the driving reality. Mathematical models of vehicle dynamic analysis including the ACC model have been constructed for computer simulation. The ACC modulates the throttle and brake functions to regulate the vehicle speed so that vehicles could keep proper spacing. Also, the real-time simulation algorithm synchronizes vehicle dynamic simulation with the graphic rendering. With the developed VR simulation system, simple scenarios are applied to analyze the dynamic characteristics. It is shown that the VR simulation system could be useful to evaluate the adaptive cruise controlled vehicle on various driving conditions.

• 한국지리정보학회지
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• 제15권2호
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• pp.150-160
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• 2012

본 연구의 목적은 경상남도 창원시에 위치한 20개 초등학교 주변 물리적 환경과 보행안전 및 교통사고 위험도와의 상호관련성을 분석하는 것이다. 현장조사는 가로 수준의 객관적, 주관적 보행환경을 평가하기 위해서 실시하였고, GIS 기법은 근린생활권 수준의 토지이용 패턴을 분석하기 위해서 사용하였다. 보행안전 및 교통사고 위험도에 관련된 자료는 18개 초등학교의 5~6학년 6,381명을 대상으로 한 설문조사를 통하여 수집하였다. 상관분석에 따르면, 가로 수준의 보도 위 영구적 장애물, 차량 진 출입구, 조명시설, 교통안전표지, 그리고 근린생활권 수준의 단독주택 및 도로면적율 등은 보행안전 또는 교통사고 위험도와 높은 상관성을 가지는 것으로 분석되었다. 향후 본 연구는 안전한 통학로와 보행친화적인 건강한 커뮤니티를 조성하는데 활용 가능할 것으로 판단된다.

• 한국항해항만학회지
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• 제32권5호
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• pp.321-326
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• 2008

최근 국내에서는 원활한 물류 수송과 도로 이용자의 편의를 도모하기 위해 항만 및 주요 항로를 횡단하는 대형 해상교량 건설이 활발하게 추진되고 있다. 그러나 이러한 해상교량건설이 육상 도로시스템의 연장선상에서 경제 원리에 입각하여 추진된다면 이는 해상교통안전 확보에 지장을 초래할 수도 있을 것이다. 이러한 위험요소를 사전에 검증하고 통항안전성 유무를 평가하기 위하여 대표적인 방법으로 선박조종시뮬레이션을 채택하고 있다. 본 연구에서는 국내 전 기능 선박조종시뮬레이터(FMSS)를 보유하고 있는 대표 4개 기관에서 해상교량 건설과 관련하여 수행했던 통항안전성 평가 보고서를 비교 분석하여, 각 기관별 수행 방법에 대한 차이점과 문제점을 도출하고, 향후 시뮬레이션의 수행 및 평가 방법에 대한 표준화 필요성을 제시하고자 한다.